Bacillus sp d747 strain, plant disease controllring agents and insect pest controlling agents using the same and control method using the agents

ABSTRACT

The present invention relates to a novel strain of  Bacillus  sp. D747 (FERM BP-8234). In addition, the present invention also relates to an agent for controlling plant diseases and an agent for controlling insect pests, comprising the  Bacillus  sp. D747 strain, and relates to a control method using the agents described above. By administering cultures of  Bacillus  sp. D747 (including the viable bacteria) or viable bacteria isolated by culturing, on the plant parts such as roots, stems, leaves, seeds, and the like, or in the culture soil, outbreaks of various plant diseases in an extremely wide range can be controlled, and pests can also be controlled. In addition, the plants on which the agents for controlling plant diseases and the agents for controlling pests comprising the D747 strain according to the present invention have been sprayed can exhibit superior controlling effects with respect to various plant diseases and pests.

TECHNICAL FIELD

[0001] The present invention relates to a Bacillus sp. D747 strain andto applications thereof. More particularly, the present inventionrelates to an agent for controlling a plant disease and/or an agent forcontrolling an insect pest comprising, as an active bacterium, theBacillus sp. D747 strain exhibiting effects of controlling plantdiseases and effects of controlling pests, and relates to a controlmethod using these control agents.

BACKGROUND ART

[0002] As examples of methods for controlling plant diseases and pests,mention may be made of physical control methods and field husbandrycontrol methods which employ crop rotation or solar heating, chemicalcontrol methods using agrichemicals, control methods utilizingdisease-resistant varieties, biological control methods using attenuatedviruses or antagonistic microorganisms on pathogenic fungi, and thelike. Among these methods, research and development for agrichemicalsand particularly organo-synthetic fungicides have been significantlyimproved in recent years, and many agents having high potency andexhibiting various effects are continuously being developed.Furthermore, various application methods have also been provided. Thechemical control methods using these have greatly contributed tocontrolling plant diseases, saving labor in controlling operations, andthe like, and have been widely employed. However, recently, it isobserved in some crop plants and diseases that controlling effectsprovided by chemical control methods are reduced due to the appearanceof so-called chemical-resistant pests, and this has become a problem. Inaddition, as a result of continuous cropping forced by spreading ofmonocultures, outbreaks of infectious diseases via soil, which arebelieved to be difficult to control with agrichemicals, have become aserious problem in various locations. Furthermore, in methods in whichlarge amounts of agrichemicals are repeatedly employed, chemicalsubstances, which are not naturally present, are released into theenvironment. For this reason, it has been understood that not onlychemicals which are directly toxic to animals and plants, but alsonon-toxic chemicals, can cause adverse effects on the environment.

[0003] As described above, the control of diseases with agrichemicals ishighly likely to reduce controlling effects due to the appearance ofresistant pests. In this case, it is necessary to develop newfungicides. In addition, with respect to controlling diseases which arebelieved to be difficult to control with agrichemicals, alternativemeans or means used together with other methods must be implemented. Inaddition, it is desired that a control technique which is safer in viewof the environment be established.

[0004] Recently, in light of these circumstances, controlling methodsdepending on the use of agrichemicals are being reconsidered, andbiological control methods utilizing microorganisms (so-calledbiological control agents) which are believed to be safer for theenvironment compared with agrichemicals have been proposed, and some ofthese have been put to practical use.

[0005] In research for biological control of plant diseases, utilizationof attenuated viruses, utilization of attenuated pathogenic ornon-pathogenic type microorganisms of pathogenic microbes, utilizationof antagonistic microorganisms, and the like, have been attempted. Amongthese, there is much research on utilization of antagonisticmicroorganisms. In addition, there are many reports on research forcontrolling diseases among the antagonistic microorganisms in the genusBacillus. However, the genus Bacillus has not been found to exhibiteffects for controlling a broad spectrum of diseases.

DISCLOSURE OF THE INVENTION

[0006] An object of the present invention is to isolate a novel strainexhibiting effects of controlling diseases of plural varieties of plantdiseases and/or controlling insect pests.

[0007] Another object of the present invention is to provide an agentfor controlling a plant disease and/or an agent for controlling aninsect pest, comprising, as an active bacterium, the aforementionedstrain, which can be effectively employed as a biological control agent.

[0008] Another object of the present invention is to provide a methodfor controlling plant diseases and/or insect pests using the agent forcontrolling a plant disease and/or the agent for controlling an insectpest described above.

[0009] The present inventors discovered that a novel strain belonging tothe genus Bacillus isolated from nature exhibits effects of controllingseveral varieties of plant diseases and exhibits effects of controllingpests without harming plant growth, thus completing the presentinvention.

[0010] The present invention relates to a strain described below, anagent for controlling a plant disease and/or an agent for controlling aninsect pest, and a method for controlling plant diseases and/orcontrolling insect pests.

[0011] (1) A Bacillus sp. D747 strain.

[0012] (2) An agent for controlling a plant disease characterized bycomprising the Bacillus sp. D747 strain as an active bacterium.

[0013] (3) An agent for controlling an insect pest characterized bycomprising the Bacillus sp. D747 strain as an active bacterium.

[0014] (4) A method for controlling a plant disease and/or an insectpest characterized by employing the agent for controlling a plantdisease described in (2) above and/or the agent for controlling aninsect pest described in (3) above.

[0015] [Isolation of the Bacillus sp. D747 Strain and DepositionThereof]

[0016] The Bacillus sp. D747 strain of the present invention is a strainisolated from the air in Kikugawa-cho, Ogasa-gun, Shizuoka-ken, JAPAN.As a result of identification of the strain in view of the bacterialcharacteristics described below in accordance with Bergey's Manual ofSystematic Bacteriology, Volume 1 (1984), it was believed that it was anovel strain belonging to the genus Bacillus, and might be a Bacilluscereus. For this reason, the strain was deposited as “Bacillus cereusD747” at the Agency of Industrial Science and Technology, NationalInstitute of Bioscience and Human Technology, on Nov. 28, 2000.

[0017] However, after that, it was again studied in detail as to whetheror not it belonged to Bacillus cereus. As a result, the study providedonly the confirmation that it belonged to the genus Bacillus. For thisreason, a notification of change of the name of the strain to “Bacillussp. D747” was submitted on Apr. 1, 2002.

[0018] Therefore, the Bacillus sp. D747 strain (hereinafter, simplyreferred to as the “D747 strain”) according to the present invention wasdeposited at the National Institute of Advanced Industrial Science andTechnology, International Patent Organism Depositary as “Bacillus sp.D747” with Accession Number “FERM P-18128”, and was then transferred tobe deposited under the Budapest Treaty on Nov. 8, 2002, as “Bacillus sp.D747” with new Accession Number “FERM BP-8234”.

[0019] [Bacterial Characteristics of the D747 Strain]

[0020] The bacterial characteristics of the D747 strain according to thepresent invention are described as follows. The tests for the bacterialcharacteristics were carried out in accordance with Bergey's Manual ofSystematic Bacteriology mentioned above.

[0021] (A) Morphological Characteristics

[0022] Morphology: bacillus

[0023] Size: width=1.0 to 1.2 μm; length=3 to 5 μm

[0024] Mobility: +

[0025] Flagellar adherent condition: periphery flagella

[0026] Endospore: +

[0027] Spore position: center

[0028] Spore swelling: −

[0029] (B) Cultural Characteristics

[0030] Color of colony: white to pale brown

[0031] Culturing in a bouillon agar plate medium: A white to creamcolored colony is formed, and the surface thereof is wrinkled.

[0032] (C) Physiological Characteristics

[0033] Gram's stain stainability: +

[0034] Nitrate reduction: +

[0035] MR test: −

[0036] VP test: +

[0037] Indole formation: −

[0038] Starch hydrolysis: +

[0039] Citric acid assimilating ability: +

[0040] Inorganic nitrogen source: +

[0041] Oxidase: −

[0042] Calatase: +

[0043] Growth pH 6.8, bouillon medium: +

[0044] Growth pH 5.7, bouillon medium: +

[0045] Growth temperature, 30° C.: +

[0046] Growth temperature, 50° C.: −

[0047] Growth NaCl concentration, 2%: +

[0048] Growth NaCl concentration, 5%: +

[0049] Growth NaCl concentration, 7%: +

[0050] Aerobic growth: +

[0051] Anaerobic growth: −

[0052] O-F test: O

[0053] York reaction: −

[0054] Acid formation from glucose: +

[0055] Acid formation from mannitol: −

[0056] Acid formation from L-arabinose: −

[0057] Acid formation from D-xylose: −

[0058] Gas formation from glucose: −

[0059] β-galactosidase: −

[0060] NaCl and KCl requiring property: −

[0061] [Culturing of the D747 Strain]

[0062] In the culturing method of the D747 strain employed in thepresent invention, the kinds of media, culturing conditions, and thelike, can be appropriately selected. As examples of media, mention maybe made of, for example, a medium including glucose, peptone, and ayeast extract, and the like, in addition to a common medium such as abouillon medium. In addition, solid media such as a slant medium, aplate medium, and the like, including agar, in addition to a liquidmedium, may be employed. By culturing, the D747 strain multiplies, sothat a desirable amount of the strain can be obtained.

[0063] As a carbon source of the medium, all materials into which theaforementioned strain can assimilate may be utilized. As examplesthereof, mention may be made of various synthetic or natural carbonsources which the D747 strain can utilize, in addition to sugars such asglucose, galactose, lactose, sucrose, maltose, a malt extract, and astarch hydrolysate.

[0064] As a nitrogen source of the medium, organic nitrogen-containingproducts such as peptone, bouillon, yeast extract, and the like, andvarious synthetic or natural products which the D747 strain is capableof utilizing can be utilized.

[0065] In accordance with common methods for culturing microorganisms,inorganic salts such as sodium chloride, phosphates, or the like; saltsof a metal such as calcium, magnesium, iron, or the like; micronutrientsources such as vitamins, amino acids, or the like; can be added, ifnecessary.

[0066] Culturing can be carried out under aerobic conditions such asshake culturing, aeration culturing, or the like. The culturingtemperature ranges from 20 to 30° C., and preferably ranges from 25 to30° C.; the pH ranges from 5 to 8, and preferably ranges from 6 to 7;and the culturing period suitably ranges from 1 to 4 days, andpreferably ranges from 2 to 3 days.

[0067] The Bacillus sp. D747 strain according to the present inventionexhibits properties of controlling various plant diseases andcontrolling pests by administering cultures thereof (including thebacteria per se) or treated products thereof (a mixture of a culture andother ingredients, or the like), or bacteria isolated by culturing(bacteria obtained by treating a culture by centrifugation, or cleansedbacteria thereof, or the like) or treated products thereof (a mixture ofthe isolated bacteria and other ingredients, or the like), or treatedproducts of those described above (a diluted product thereof with aliquid or a solid, or the like), on the plant parts such as roots,stems, leaves, seeds, and the like, or in the culture soil.

[0068] The D747 strain of the present invention can control plantdiseases caused by bacteria and fungi belonging to genera Oomycetes,Ascomycetes, Basidiomycetes, and Deuteromycetes.

[0069] As examples of pest fungi causing diseases which the D747 straincan control, mention may be made of, for example, Pseudoperonospora suchas Pseudoperonospora cubensis, Venturia such as Venturia inaequalis,Erysiphe such as Erysiphe graminis, Pyricularia such as Pyriculariaoryzae, Botrytis such as Botrytis cinerea, Rhizoctonia such asRhizoctonia solani, Puccinia such as Puccinia recondite, Septoria suchas Septoria nodorum, Sclerotinia such as Sclerotinia sclerotiorum,Pythium such as Pythium debaryanum Hesse; as bacteria, Burkholderia suchas Burkholderia plantarii; and the like. It should be understood thatthey are not limited to these examples in the present invention.

[0070] In addition, the D747 strain of the present invention can controlpests such as hemipterous pests, lepidopterous pests, coleopterouspests, dipterous pests, orthopteran pests, isopterous pests,thysanopterous pests, tetranychidaeous pests, and the like.

[0071] As examples of pests which the D747 strain can control, mentionmay be made of, for example, hemipterous pests including Pentatomidae(Heteroptera) such as Riptortus clavatus and the like, Cicadellidae suchas Nephotettix cincticeps and the like, Delphacidae such as Nilaparvatalugens and the like, Psyliidae such as Psylla sp., and the like,Aleyrodidae such as Bemisia tabaci and the like, Aphididae such as Myzuspersicae and the like, Pseudococcoidae such as Pseudococcus comstockiand the like; lepidopterous pests including Torticoidea such as HomonaMagnanima and the like, Cochylidae such as Eupoecillia ambiguella andthe like, Psychidae such as Bambalina sp., and the like, Gracillariidaesuch as Nemapogon granellus and the like, Phyllocnistinae such asPhyllocnistis citrella and the like, Yponomeutidae such as Plutellaxylostella and the like, Pyralidae such as Chilo suppressalis and thelike, Noctuidae such as Heliothis virescens and the like; coleopterouspests including Scarabaeidae such as Anomala cuprea and the like,Coccinellidae such as Epilachna vigintioctopunctata and the like,Curculionidae such as Lissorhoptrus oryzophilus and the like; dipterouspests such as Culex pipiens, Anopheles sinensis, Culextritaeniorhynchus, and the like; orthopteran pests such as Blatellagermanica, and the like; isopterous pests such as Reticulitermessperatus, and the like; thysanopterous pests such as Scirtothripsdorsali, and the like; tetranychidaeous pests such as Tetranychusurticae, and the like; other harmful animals, creatures to be repelled,insect pests in view of sanitation, parasites, examples of which includeGastropoda such as Pomacea canaliculat, Incilaria sp., and the like; andIsopoda such as Armadillidium sp., and the like. It should be understoodthat the present invention is not limited to these examples.

[0072] Agents for Controlling Plant Diseases and Agents for ControllingPests

[0073] The agents for controlling plant diseases and agents forcontrolling pests according to the present invention comprise, as anactive bacterium, the D747 strain which can control plant diseases andinsect pests as described above. In the agents for controlling plantdiseases and agents for controlling pests of the present invention, theD747 strain can be employed alone or in combination with a variant ofthe D747 strain. The variants have the bacterial characteristics of theD747 strain described above, exhibit effects of controlling plantdiseases, and exhibit effects of controlling pests. Spontaneous mutantstrains, mutant strains produced by using UV rays or chemical mutagenagents, cell fusion strains, and genetic recombination strains can beutilized therefor. In the present invention, the D747 strain containedin the agents for controlling plant diseases and the agents forcontrolling pests also include the variants of the D747 strain.

[0074] The term “controlling” in the specification is used to mean notonly preventing and repelling diseases or pests, but also removing anddestroying them. Therefore, even for plants which have been infected bypathogenic fungi, if the agents for controlling plant diseases areapplied thereto, the pathogenic fungi can be removed from the plants,and thereby, pathogeny caused by the pathogenic fungi and deteriorationof the diseases can be prevented. In addition, pests can also becontrolled due to the effects of repelling and killing pests.

[0075] For the case in which the D747 strain is included as viablemicroorganisms in the agents for controlling plant diseases and theagents for controlling insect pests according to the present invention,it is preferable that the strain be applied to the plant body at aconcentration ranging from 10⁵ to 10¹⁰ microorganisms/ml.

[0076] In addition, for the case in which a culture of the D747 strainis employed, the application timing and the application quantity thereofmay be appropriately determined in accordance with the case of theviable microorganisms described above.

[0077] In addition, in the agents for controlling plant diseases and theagents for controlling insect pests according to the present invention,the D747 strain may be employed alone as the strain, or a culturethereof may be employed, as formulations in which the strain is dilutedwith an inert liquid or solid carrier, and surfactants and otherauxiliary agents are added thereto, if necessary. As examples offormulations, mention may be made of granules, fine powders, wettablepowders, suspensions, emulsifiable concentrates, and the like. Asexamples of preferable carriers, mention may be made of porous solidcarriers such as talc, bentonite, clay, kaolin, diatomaceous earth,white carbon, vermiculite, slaked lime, siliceous sand, ammoniumsulfate, and urea; liquid carriers such as water, isopropyl alcohol,xylene, cyclohexanone, methylnaphthalene, and alkyl glycol; and thelike. As examples of surfactants and dispersants, mention may be madeof, for example, dinaphthylmethanesulfonates, alcohol sulfates, alkylaryl sulfonates, lignin sulfonates, polyoxyethylene glycol ethers,polyoxyethylene alkyl aryl ethers, polyoxyethylene sorbitanmonoalkylates, and the like. As examples of auxiliary agents, mentionmay be made of carboxymethylcellulose, polyethylene glycol, propyleneglycol, gum arabic, xanthan gum, and the like. As examples of protectiveagents, mention may be made of skim milk, pH buffers, and the like. Inthis case, the amount of the viable microorganisms of the D747 strainand/or the amount of the cultures thereof, the application timing, andthe application quantity can be appropriately determined in accordancewith the case of the viable microorganisms described above.

[0078] Furthermore, the agents for controlling plant diseases and theagents for controlling pests according to the present invention mayinclude other ingredients such as pesticides, other fungicides,herbicides, plant growth modifiers, fertilizers and manures, and thelike, as active ingredients, if necessary. In addition, the agents forcontrolling plant diseases and the agents for controlling insect pestsaccording to the present invention may include different varieties ofstrains from the D747 strain, together with the D747 strain.

[0079] The agents for controlling plant diseases and the agents forcontrolling insect pests according to the present invention can bedirectly applied or can be applied after diluting the agents with wateror the like. The methods for applying the agents for controlling plantdiseases and the agents for controlling insect pests are notparticularly limited. As examples thereof, mention may be made of, forexample, a method in which they are directly sprayed to plants or insectpests, a method in which they are sprayed on soil, a method in whichthey are added to water or fertilizers and manures to be applied to theplants or soil, and the like. In addition, the amount of appliedformulations will vary depending on the diseases to be controlled,insect pests to be controlled, plants to which they are to be applied,application methods, the nature of occurrence of the diseases or pests,the degree of damage, environmental conditions, the forms offormulations to be used, and the like. For this reason, it is preferablethat the amount of the applied formulations be appropriately adjusted.

[0080] As described above, the Bacillus sp. D747 strain of the presentinvention controls a wide spectrum of diseases and pests, and cancontrol multiple varieties of plant diseases and pests.

[0081] The agents for controlling plant diseases and the agents forcontrolling pests comprising the D747 strain according to the presentinvention can control plant diseases and pests. For this reason, theycan be employed as biological control agents. Therefore, the agents forcontrolling plant diseases and the agents for controlling insect pestsof the present invention are highly safe with respect to theenvironment, and exhibit effects of controlling multiple varieties ofdiseases and pests. For this reason, they can widely prevent diseasesand pests without employing other means for simultaneous use therewith.

BEST MODES FOR CARRYING OUT THE INVENTION

[0082] The present invention is described in detail be means of theExamples described below. However, it should be understood that thepresent invention is not limited to these Examples.

EXAMPLE 1 Culturing of the D747 Strain

[0083] The D747 strain was isolated from the air in Kikugawa-cho,Ogasa-gun, Shizuoka-ken, JAPAN. More particularly, in order to isolatethe microorganisms present in the air at Kamo, Kikugawa-cho, Ogasa-gun,Shizuoka-ken, JAPAN, a plate medium containing a potato-dextrose agarwas allowed to stand for 10 minutes with the lid off so as to be incontact with the air. The medium was incubated for 3 days at 27° C., andthe formed colony was isolated. The isolated colony was incubated with ashaker in a medium of a potato-dextrose liquid. The strain exhibitingactivities with respect to plant diseases was discovered, thus resultingin isolation of the D747 strain.

[0084] The isolated D747 strain was incubated at 27° C. on a rotaryshaker at 120 rpm for 3 days in a medium having a pH of 6.0 andcomprising 1% of glucose, 2% of a soluble starch, 0.5% of polypeptone,1% of a dry yeast, 1% of defatted soybeans, 0.2% of KH₂PO₄, 0.2% ofNaCl, and 0.3% of calcium carbonate. Subsequently, the strains werecollected by centrifugation (10,000×g, for 15 minutes), were suspendedin sterilized water, and were washed to remove the medium ingredients.The serial procedures described above were repeated twice. Subsequently,the strains were again suspended in sterilized water at a concentrationof approximately 10⁹/ml.

EXAMPLE 2 Test on the Effects of Controlling Infection by Rice Blast

[0085] Rice seeds (variety: Aichi Asahi) were sown at a rate of 10grains each in clay pots having a diameter of 7.5 cm, and were allowedto grow in a greenhouse. A suspension of the D747 strains produced asdescribed in Example 1 was sprayed at a rate of 10 ml per pot on therice seedlings at their 4-leaf stage. After being dried in the air, theseedlings were inoculated by spraying a spore suspension of rice blast(Pyricularia oryzae) fungi, and were placed in a moist chamber. On thefifth day after the inoculation, the number of lesions on the fourthleaf was counted, and was evaluated as the extent of lesions on thebasis of the evaluation criteria shown in Table 1 described below. Thetest results are shown in Table 2. TABLE 1 Evaluation A No lesions wereobserved. B Less than 20% based on the extent of lesions in theuntreated plot C 20% or more but less than 50% based on the extent oflesions in the untreated plot D 50% or more based on the extent oflesions in the untreated plot

EXAMPLE 3 Test on the Effects of Controlling Infection by Rice SheathBlight

[0086] Rice seeds (variety: Kinmaze) were sown at a rate of 10 grainseach in clay pots having a diameter of 6.0 cm, and were allowed to growin a greenhouse. A suspension of the D747 strains produced as describedin Example 1 was sprayed at a rate of 10 ml per pot on the riceseedlings at their 2-through 3-leaf stages. After being dried in theair, the seedlings were inoculated with rice sheath blight(Thanatephorus cucumeris) fungi, and were placed in a moist chamber. Onthe fifth day after the inoculation, the heights of lesions weremeasured, and were employed as an evaluation of the extent of lesions.Evaluation was carried out on the basis of the evaluation criteria shownin Table 1 described above. The test results are shown in Table 2.

EXAMPLE 4 Test on the Effects of Controlling Infection by Wheat GlumeBlotch

[0087] Wheat seeds (variety: Nourin No. 61) were sown at a rate of 10grains each in plastic pots having a diameter of 6.0 cm, and wereallowed to grow in a greenhouse. A suspension of the D747 strainsproduced as described in Example 1 was sprayed at a rate of 10 ml perpot on the wheat seedlings at their 2-leaf stage. After being dried inthe air, the seedlings were inoculated with pycnospores of wheat glumeblotch (Septoria nodorum) fungi, and were placed in a greenhouse. On thetenth day after the inoculation, the infected area of the first leaf ineach pot was measured, and was employed as an evaluation of the extentof lesions. Evaluation was carried out on the basis of the evaluationcriteria shown in Table 1 described above. The test results are shown inTable 2.

EXAMPLE 5 Test on the Effects of Controlling Infection by Wheat PowderyMildew

[0088] Wheat seeds (variety: Nourin No. 61) were sown at a rate of 10grains each in plastic pots having a diameter of 6.0 cm, and wereallowed to grow in a greenhouse. A suspension of the D747 strainsproduced as described in Example 1 was sprayed at a rate of 10 ml perpot on the wheat seedlings at their 1.5- through 2-leaf stages. Afterbeing dried in the air, the seedlings were inoculated with conidiosporesof wheat powdery mildew (Erysiphe graminis), and were placed on a benchin a greenhouse until an infection measurement was carried out. On thetenth day after the inoculation, the infected area of the first leaf ineach pot was measured, and was employed as the extent of lesions.Evaluation was carried out on the basis of the evaluation criteria shownin Table 1 described above. The test results are shown in Table 2.

EXAMPLE 6 Test on the Effects of Controlling Infection by Cucumber GrayMold

[0089] Cucumber seeds (variety: Sagami Hanjiiro) were sown at a rate of4 grains each in plastic pots having a diameter of 6.0 cm, and wereallowed to grow in a greenhouse. A suspension of the D747 strainsproduced as described in Example 1 was sprayed at a rate of 10 ml perpot on the young cucumber seedlings in their cotyledonous stage. Afterbeing dried in the air, the seedlings were inoculated by placing a paperdisk which was immersed in a spore suspension of cucumber gray mold(Botrytis cinerea) fungi on the surface of the cotyledons of thecucumber seedlings, and were subsequently placed in a moist chamber at20° C. On the third day after the inoculation, the infected area of thecotyledons was measured, and was employed as an evaluation of the extentof lesions. Evaluation was carried out on the basis of the evaluationcriteria shown in Table 1 described above. The test results are shown inTable 2.

EXAMPLE 7 Test on the Effects of Controlling Infection by Cucumber DownyMildew

[0090] Cucumber seeds (variety: Sagami Hanjiiro) were sown at a rate of4 grains each in plastic pots having a diameter of 6.0 cm, and wereallowed to grow in a greenhouse. A suspension of the D747 strainsproduced as described in Example 1 was sprayed at a rate of 10 ml perpot on the young cucumber seedlings in their cotyledonous stage. Afterbeing dried in the air, the seedlings were inoculated by spraying azoosporangium suspension of cucumber downy mildew (Pseudoperonosporacubensis) fungi, and were subsequently allowed to stand in a moistchamber at 22° C. for 24 hours. On the eighth day after the inoculation,the infected area of the cotyledons was measured, and was employed as anevaluation of the extent of lesions. Evaluation was carried out on thebasis of the evaluation criteria shown in Table 1 described above. Thetest results are shown in Table 2. TABLE 2 Example Plant Controllingeffect No. disease tested by the D747 strain 2 rice blast A 3 ricesheath blight A 4 wheat glume blotch A 5 wheat powdery mildew A 6cucumber gray mold A 7 cucumber downy mildew A

EXAMPLE 8 Mortality Test of Lissorhoptrus oryzophilus

[0091] A suspension of the D747 strain produced as described in example1, in an amount of 30 ml, was placed in a plastic cup having a volume of60 ml. Three pieces of rice leaves having a length of 3 cm were floatedthereon. Ten imagoes of Lissorhoptrus oryzophilus were released therein,and the cup was closed with a cover. After it was allowed to stand in athermostatic chamber at 25° C. for 3 days, the number of living pestswas counted. The test was carried out three times. A mortality rate wascalculated by equation (1) described below. A definitive mortality ratewas determined by calculating an average value of the three values. Thetest results are shown in Table 3.

Mortality rate(%)={[10−(the number of living pests)]/10}×100 TABLE 3Definitive mortality rate (%) Treated with the D747 strain 100 Notreatments 0

[0092] As is apparent from the results shown in Table 2 and Table 3, theplants to which the agents for controlling plant diseases and the agentsfor controlling insect pests comprising the D747 strain according to thepresent invention were applied exhibited superior controlling effectswith respect to various plant diseases and pests.

INDUSTRIAL APPLICABILITY

[0093] The present invention has characteristics in that a novel strainof Bacillus sp. D747 (FERM BP-8234) was discovered. By administeringcultures of the Bacillus sp. D747 strain (including the viable bacteria)or viable bacteria isolated by culturing, on plant parts such as roots,stems, leaves, seeds, and the like, or in the culture soil, outbreaks ofvarious plant diseases in an extremely wide range can be controlled, andpests can be controlled. In addition, the plants on which the agents forcontrolling plant diseases and the agents for controlling insect pestscomprising the D747 strain according to the present invention aresprayed can exhibit superior controlling effects with respect to variousplant diseases and pests.

1. A Bacillus sp. D747 strain.
 2. An agent for controlling a plantdisease characterized by comprising a Bacillus sp. D747 strain as anactive bacterium.
 3. An agent for controlling an insect pestcharacterized by comprising a Bacillus sp. D747 strain as an activebacterium.
 4. A method for controlling a plant disease and/or an insectpest, characterized by employing the agent for according to claim 2.